Calculating Distance to Make a Catch using Laws of Cosines

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AI Thread Summary
The discussion revolves around using the Law of Cosines to calculate the distance a center field player must run to catch a fly ball. Given the distances from the camera to the player and the wall, along with the angle of 6 degrees, the problem is set up as a SAS case. The user correctly applies the first equation of the Law of Cosines to find the distance, resulting in an approximate answer of 98.07 feet. The calculations are confirmed as correct, and the user notes the consideration of negative roots, emphasizing that only the positive distance is relevant in this context. The solution effectively demonstrates the application of trigonometric principles in a real-world scenario.
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Homework Statement


The problem has to do with laws of cosines/sines.

"The baseball player in center field is playing approximately 330 feet from the television camera that is behind home plate. A batter hits a fly ball that goes to the wall 420 feet from the camera. The camera turns 6 degrees to follow the play. Approximate the distance the center field has to run to make the catch."

The diagram given looks roughly like this:
http://img151.imageshack.us/my.php?image=fieldbu9.jpg

Homework Equations



There are 3 equations relating to the Laws of Cosines:

1. a^2 = b^2 + c^2 - 2bccos(A)
2. b^2 = a^2 + c^2 - 2accos(B)
3. c^2 = a^2 + b^2 - 2abcos(C)


The Attempt at a Solution



At this point the case of this problem is SAS (side side angle). So I know that laws of cosines has to be used here.

I then labeled the diagram like this:
http://img525.imageshack.us/my.php?image=field2uv3.jpg

Givens:
b=420
c=330
A=6 degrees
a = ?

a is what needs to be solved.

I then used equation one since it has the most related givens

a^2 = b^2 + c^2 - 2bccos(A)
a^2 = 420^2 + 330^2 - 2(420)(330)cos6

a = \sqrt{420^2 + 330^2 - 2(420)(330)cos6}

a = 98.07ft

Thats my approximate answer. Can someone verify it?
 
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The expression in the root is correct.
 
So is everything correct?
 
Since you are taking the root of a number it should be +-. But negative distance doesn't make sense, but it is something to keep in mind.
 
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